Yes, of course you are correct, xvimbi, and people who disagree with you should definitely not attempt the Liszt exercises. One should allot as much focus and energy on the exercises--assuming he wants to--as on regular pieces, and play them with the utmost carefulness.
Of course I also say that once the pianist plays each exercise with 100% correctness and accuracy (a good indicator of this for me is to be able and play each exercise at a slightly upbeat moderato tempo without strain or tension, both of which the pianist *should* be capable of identifying), the exercises become relatively useless. Now of course I didn't get quite up to that level myself, but that's probably because my technical ambitions are low compared to my desire to perform, for the time being. Besides, college is coming up quickly and I'm not majoring in music so...I'll let that speak for itself!